net/nfp: use ethdev DMA helper
net/nfp: use ethdev DMA helper

This driver can use the library function rte_eth_dma_zone_reserve()
instead of duplicating the code.

Signed-off-by: Jan Blunck <428a1e03bf18d7720952a3563b48222e4a94a135@infradead.org>
Acked-by: Stephen Hemminger <06fa905d7f2aaced6dc72e9511c71a2a51e8aead@networkplumber.org>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk